I am considering removing my catalytic converters in place of an of road x-pipe. I was told by someone that if you remove the cats, you will have to replace the spark plugs every few thousand miles because the car will run too rich, regardless if you have O2 simulators or not. Some of you have done this modification. Could someone offer some insight on as to whether or not this is true. Also, what gains can be expected from removing them? Is it worth it?